The present invention relates to an apparatus and method for bio-assisted treatment of spent caustic obtained from hydrocarbon and gas processing installations. The present invention also relates to method for recovery of caustic and recovery of sulfur from spent caustic. According to present invention, the sulfide removal is about 96% and the sulphur formation and deposition on the electrode lies in range of 72±8%.

A deammonification system 100 and process for treating wastewater are disclosed herein. The system and process may involve an anaerobic reactor 204 operable to produce biogas 2 from organic carbon in the wastewater 1, and a deammonification unit including (i) one or more anoxic chambers 302 in fluid communication with the anaerobic reactor 204, wherein each of the one or more anoxic chambers 302 houses a plurality of biocarriers 306, wherein each of the plurality of biocarriers 306 includes a biofilm of anaerobic ammonium oxidation bacteria, and (ii) one or more oxic chambers 304 operable to produce nitrite from ammonia and/or ammonium, wherein the wastewater processed in an anoxic chamber 302 of the one or more anoxic chambers 302 is channeled to an oxic chamber 304 of the one or more oxic chambers 304 which is adjacent to and downstream of the anoxic chamber 302.

A method for achieving rapid startup of a denitrification biofilter tank, which belongs to the technical field of biofilm sewage treatment. The specific steps are: 1. selecting heterotrophic denitrification or mixotrophic denitrification to treat influent sewage; 2. when the heterotrophic denitrification is used, pretreating the filter material with sodium carboxymethyl cellulose solution and then adding rhamnolipid after the introduction of sewage until the biofilter tank system starts successfully; 3. when the mixotrophic denitrification method is used, the filter tank is inoculated after the introduction of sewage, and the rhamnolipid is added thereto and is changed to sulfur source after operation for a while until startup is complete. The invention solves the problem that the denitrification biofilter tank in the sewage treatment is particularly slow in the mixotrophic state, and has a good application prospect.

Various embodiments relate to denitrification of water using bacteria. A method of denitrification of water includes deoxygenated water including a water-soluble form of nitrogen. The method includes exposing the deoxygenated water to denitrifying bacteria to convert the water-soluble form of nitrogen in the water to nitrogen gas that is removed and to form a denitrified water. The method also includes reoxygenating the denitrified water. Denitrifying bacterial substrates and methods of making the same are also provided.

A system and method of treating wastewater. In one embodiment, the system comprises a biological reactor fluidly connected to a source of wastewater and having a treated wastewater outlet, a fixed film biological reactor connected to the source of wastewater and having a fixed film effluent outlet, and a ballasted system fluidly connected to the fixed film effluent outlet. The ballasted system may comprise a ballast reactor tank configured to provide a ballasted effluent, and a source of ballast material fluidly connected to an inlet of the ballast reactor tank. The system may further comprise a bypass line having an inlet fluidly connected to the source of wastewater, a first outlet fluidly connected to the ballasted system, and a second outlet fluidly connected to the fixed film biological reactor, the bypass line configured to bypass the fixed film biological reactor.

Methane is generated from animal waste by anaerobic digestion using bacteria. A screen separator removes suspended solids greater in size than a predetermined size ranging from about 50 .Math. to about 150 .Math.. An electrocoagulation unit electrochemically hydrolyses the waste, causing particles to settle out. A dissolved carbon air flotation has a CO.sub.2 bubbler for separating large particles from small particles by flotation. An anaerobic digester produces biogas. The digester has a biocurtain for growing the bacteria and a heat exchanger for heating the bacteria. The biocurtain surface is convoluted to retain the bacteria. A membrane module removes CO.sub.2. A knock out pot for removes droplets of water. A scrubber removes water vapor, particulates, and contaminant gas. A compressor boosts pressure. A gas chromatograph monitors the biogas composition. A flare skid lowers excess pressure for safety. Biogas is injected into a local pipeline system. A process control is used for controlling the anaerobic waste digestion system.

Methods of delivering microorganisms loaded onto an inorganic porous medium. Methods of treating wastewater to increase effluent and biosolids quality. Methods of reducing ammonia and denitrifying wastewater effluent. Methods of reducing phosphorous concentration in wastewater effluent. Composition of biosolids derived from wastewater treatment. Wastewater treatment assemblage for increasing wastewater effluent and biosolids quality.

Various embodiments relate to denitrification of water using bacteria. A method of denitrification of water includes deoxygenated water including a water-soluble form of nitrogen. The method includes exposing the deoxygenated water to denitrifying bacteria to convert the water-soluble form of nitrogen in the water to nitrogen gas that is removed and to form a denitrified water. The method also includes reoxygenating the denitrified water. Denitrifying bacterial substrates and methods of making the same are also provided.

A microbial carrier and a device for treating wastewater are provided. The microbial carrier includes a bacteriophilic material and a plurality of foam cells, wherein the foam cells are disposed in the bacteriophilic material. The bactericidal material is a reaction product of a composite, wherein the composition includes a hydrophobic polyvinyl alcohol and a cross-linking agent, wherein the surface energy of the hydrophobic polyvinyl alcohol is 30 mJ/m.sup.2 to 58 mJ/m.sup.2.

A system and method of treating wastewater. In one embodiment, the system comprises a biological reactor fluidly connected to a source of wastewater and having a treated wastewater outlet, a fixed film biological reactor connected to the source of wastewater and having a fixed film effluent outlet, and a ballasted system fluidly connected to the fixed film effluent outlet. The ballasted system may comprise a ballast reactor tank configured to provide a ballasted effluent, and a source of ballast material fluidly connected to an inlet of the ballast reactor tank. The system may further comprise a bypass line having an inlet fluidly connected to the source of wastewater, a first outlet fluidly connected to the ballasted system, and a second outlet fluidly connected to the fixed film biological reactor, the bypass line configured to bypass the fixed film biological reactor.